Rush Hour is PSAPCE-complete, or "Why you should generously tip parking lot attendants"
Theoretical Computer Science
Computers and Intractability: A Guide to the Theory of NP-Completeness
Computers and Intractability: A Guide to the Theory of NP-Completeness
Complexity of decision problems based on finite two-person perfect-information games
STOC '76 Proceedings of the eighth annual ACM symposium on Theory of computing
Composition of Motion Description Languages
HSCC '08 Proceedings of the 11th international workshop on Hybrid Systems: Computation and Control
GP-rush: using genetic programming to evolve solvers for the rush hour puzzle
Proceedings of the 11th Annual conference on Genetic and evolutionary computation
Reconfiguration of List Edge-Colorings in a Graph
WADS '09 Proceedings of the 11th International Symposium on Algorithms and Data Structures
Finding Paths between graph colourings: PSPACE-completeness and superpolynomial distances
Theoretical Computer Science
Coordination by design and the price of autonomy
Autonomous Agents and Multi-Agent Systems
On the symbolic computation of the hardest configurations of the RUSH HOUR game
CG'06 Proceedings of the 5th international conference on Computers and games
Solutions to real-world instances of PSPACE-complete stacking
ESA'07 Proceedings of the 15th annual European conference on Algorithms
Understanding planning tasks: domain complexity and heuristic decomposition
Understanding planning tasks: domain complexity and heuristic decomposition
On the complexity of reconfiguration problems
Theoretical Computer Science
Shortest paths between shortest paths and independent sets
IWOCA'10 Proceedings of the 21st international conference on Combinatorial algorithms
Approximability of the subset sum reconfiguration problem
TAMC'11 Proceedings of the 8th annual conference on Theory and applications of models of computation
An improved sufficient condition for reconfiguration of list edge-colorings in a tree
TAMC'11 Proceedings of the 8th annual conference on Theory and applications of models of computation
Complexity of independent set reconfigurability problems
Theoretical Computer Science
Complete algorithms for cooperative pathfinding problems
IJCAI'11 Proceedings of the Twenty-Second international joint conference on Artificial Intelligence - Volume Volume One
Reconfiguration of list edge-colorings in a graph
Discrete Applied Mathematics
The kissing problem: how to end a gathering when everyone kisses everyone else goodbye
FUN'12 Proceedings of the 6th international conference on Fun with Algorithms
The complexity of rerouting shortest paths
MFCS'12 Proceedings of the 37th international conference on Mathematical Foundations of Computer Science
Finding paths between graph colourings: pspace-completeness and superpolynomial distances
MFCS'07 Proceedings of the 32nd international conference on Mathematical Foundations of Computer Science
The complexity of rerouting shortest paths
Theoretical Computer Science
Hi-index | 0.00 |
We present a nondeterministic model of computation based on reversing edge directions in weighted directed graphs with minimum in-flow constraints on vertices. Deciding whether this simple graph model can be manipulated in order to reverse the direction of a particular edge is shown to be PSPACE-complete by a reduction from Quantified Boolean Formulas. We prove this result in a variety of special cases including planar graphs and highly restricted vertex configurations, some of which correspond to a kind of passive constraint logic. Our framework is inspired by (and indeed a generalization of) the "Generalized Rush Hour Logic" developed by Flake and Baum [Theoret. Comput. Sci. 270(1-2) (2002) 8951.We illustrate the importance of our model of computation by giving simple reductions to show that several motion-planning problems are PSPACE-hard. Our main result along these lines is that classic unrestricted sliding-block puzzles are PSPACE-hard, even if the pieces are restricted to be all dominoes (1 × 2 blocks) and the goal is simply to move a particular piece. No prior complexity results were known about these puzzles. This result can be seen as a strengthening of the existing result that the restricted Rush HourTM puzzles are PSPACE-complete [Theoret. Comput. Sci. 270(1-2) (2002) 895], of which we also give a simpler proof. We also greatly strengthen the conditions for the PSPACE-hardness of the Warehouseman's Problem [Int. J. Robot. Res. 3(4) (1984) 76], a classic motion-planning problem. Finally, we strengthen the existing result that the pushing-blocks puzzle Sokoban is PSPACE-complete [In: Proc. Internat. Conf. on Fun with Algorithms, Elba, Italy, June 1998, pp. 65-76.], by showing that it is PSPACE-complete even if no barriers are allowed.